Heat (Croatoan ABO 'Verse Part 1)
by addictcas
Summary: (Endverse AU) Castiel goes through his first human heat. Dean is there to help. (omega!Castiel/alpha!Dean) (part 1 of series: Croatoan ABO 'Verse) (can be read alone)


**NOTE: This story contains Alpha/Beta/Omega dynamics, including mating cycles/heat, knotting, self-lubrication, and biting/claiming. If you are not into that you probably don't want to read this. If you are, enjoy. :)**

**part 1 of series: Heat  
part 2 of series: Claim  
part 3 of series: High**

Camp Chitaqua has been out of heat suppressants for three months now; so Castiel isn't surprised when he wakes up to sheets soaked with sweat and slick, rutting against his blanket in a futile attempt to relieve the pressure that's built up in his groin. Nothing he's heard from anyone else gives justice to what he's feeling right now, like he's burning from the inside out.

He looks around at the mostly naked bodies in his bed and on the floor and sees that his scent has woken up two dark-eyed Alphas.

The Alpha in the bed next to him, Travis or Trevor or something, runs a finger down his arm. "Need help with that, sweetheart?" Castiel shrugs him off and reaches for jeans he's pretty sure belong to him. "Where're you going? I know you wanna bend over and take my knot like the bitch you are."

Castiel glares at him, disgusted. He's never been anyone's bitch and he never will be. "How charming you are."

The other Alpha who Castiel definitely can't name sidles up to him as he stands and pulls on the jeans. He puts his arms on his waist and presses his nose against Castiel's neck, inhaling deeply. "Don't pay attention to him, I'll take care of you."

Castiel pulls himself out of the Alpha's grip and grabs his t-shirt (much to the irritation of an Omega girl who was using it as a pillow). He puts it on as the second Alpha leers at him.

"What are you covering up for?"

"I'm sorry, you'll have to look somewhere else for what you want." Fuck overpowering, painful instincts, he's nowhere near horny enough to put up with this bullshit.

"C'mon, we all know you're the camp slut."

Castiel doesn't exactly have a strong argument against that that so he simply smiles and holds up his middle finger as he makes his way out of the bedroom.

He needs to find Dean. He needs Dean to soothe the flames that are singing every nerve ending, to pull him from this Hell just as Castiel raised Dean from perdition all those years ago. He knows no other Alpha will satisfy his cravings. He only hopes Dean will want him, too.

Fingernails dig into his palms as his stomach twists nervously. Castiel is afraid of rejection. He's afraid that this will change things for the worse, that Dean will distance himself even further than he had the day Sam had said "yes." He bounces on the balls of his feet a few times before he musters up the courage to knock on the door of Dean's cabin.

It takes a minute for the door to swing open, but when it does Dean's nostrils flare and his pupils dilate. He grips the front of Castiel's shirt and drags him inside, slamming the door behind him. The intoxicating scent of alpha, of _aroused _alpha, washing over Cas' senses causes blood to flow downward into his already throbbing cock.

"The hell are you doin' walking around outside smelling like that." He's leans forward a bit and Castiel can tell he resisting the urge to scent him. Dean's brow furrows into a deep frown that doesn't make him any less infuriatingly attractive.

"My cabin was… compromised." None of them were _you_.

"Of course it was," Dean snaps, and Castiel can hear… jealousy?

Here goes nothing. "I would like your help." Castiel steps forward and Dean moves away, glaring at him.

"Why don't you get one of your '_disciples_' to fuck you?"

"I don't want any of them," he says, cupping Dean's jaw in a surprisingly tender gesture. Castiel doesn't usually _do_ tender. "I want you."

_I love you._

Castiel steps into Dean's personal space and this time Dean doesn't back away, letting Cas lean in so that their faces are mere inches apart.

"How long?" Dean croaks.

Castiel thinks back, tries to remember when he had fallen and broken beyond repair. "Since the green room."

"Fuck, Cas." Something in Dean breaks then and he buries his face in Castiel's neck, breathing him in. "You smell incredible."

Castiel groans as he feels Dean's arousal pressed against his own. It's a good sign, but he needs to know something before they can move things further.

"Would you want this, Dean, if I wasn't in heat?"

Dean's hands are on his ass now and he growls when he feels the patch where Castiel's slick has soaked through the denim of his jeans. "I've wanted this for as long as you have."

"Then tell me why we didn't do this soon–" Castiel is cut off roughly by a kiss. It's harsh and possessive and makes him feel like he's flying, more than any chemical that has pumped through his veins. He's glad he hasn't taken anything recently because he needs to be here, one hundred percent. Castiel needs to feel every flick of Dean's tongue, every fingernail scraping against his sweat-slick skin as Dean pulls his shirt over his head.

Castiel wraps his legs around Dean's waist as he's picked up and carried to the bedroom. The liplock they've entangled themselves in stays intact until Dean drops the omega on the bed and unzips his jeans.

"Commando, Cas? Really?"

Castiel tilts his head because he's not really sure what that means, and the alpha laughs at him as he peels the pants off.

Dean takes a few moments to just look at him with those lust-blown green eyes and Castiel squirms uncomfortably. He feels raw, exposed, and yet Dean is standing there fully clothed, just staring at him.

"I'm feeling a little under dressed for this party right now."

That seems to break Dean out of whatever weird little trance he was under. "Right, sorry." The alpha makes quick work of removing his clothes and crawling onto the bed. Their lips meet again for a desperate kiss, all teeth and tongue, and it's wonderful but not nearly enough for Castiel.

"Hurry up and get your fingers in me, Dean."

The other man looks at him with raised eyebrows. "You know, you're really _bossy_ for an omega."

"Bite me," he retorts, realizing the other connotation a second too late. Dean makes nothing of it, though, nipping his ear playfully. He runs over the shell with his tongue and Castiel digs his fingers into Dean's shoulders. "I said hurry up."

Dean huffs out an amused sigh. "Okay, okay."

He doesn't fucking listen, though. He places a hand on Castiel's chest, right above his heart, and trails his fingers slowly, so slowly, down his body. He dips into the omega's navel, then through the thin trail of hair underneath, and when he finally reaches his cock it's just a light skimming over the heated flesh. Castiel tries to press into it, to get some kind of friction, but by the time he moves the hand is giving his balls the same treatment. The touches offer no relief. They only fuel the aching want inside of him.

Dean is shamelessly grinding against his thigh by the time he gets his fingers where Castiel wants them. Still, the finger only circles the rim lightly.

Castiel tries to push down onto it. "Dean."

"I've got you, baby, relax" he says, and he slides his finger all the way in. Normal Cas doesn't like endearments, finds names like 'sweetheart' and 'baby' condescending at best, especially coming from an alpha to an omega, but from Dean it brings him a sense of just being wanted, cared for.

"Jesus, you're tight."

"I've never been fucked before," Castiel blurts out, before he can stop himself.

He can only find it in himself to regret his over-sharing for a few moments before Dean lights up like a fucking kid on Christmas morning. "Really?"

Castiel feels his face heating up. "I've been with plenty of guys, sure, and plenty of _alphas_ at that. But I've never let them– I only ever wanted you, I guess." He's embarrassed until Dean speaks up.

"I've uh, never been with a guy, period." Castiel isn't very surprised by this; when he was an angel and could see into Dean's mind he discovered that despite having plenty of bisexual curiosities, he had never acted upon any of them. But Castiel hadn't known for sure that that still remained true.

He feels a surge of possessiveness at Dean's confession. They're both _far_ from virgins, but this is something they share only with each other, and that warms him from the inside out. Castiel kisses him fiercely, trying to convey his happiness with what he just learned. Dean gives back as good as he gets and adds another finger. His lips move from Castiel's mouth to his jaw, pressing hot kisses against his stubbled skin, then get to his neck and suck. _Hard_. Castiel knows he'll be proudly wearing that mark for at least a week and a half.

Dean suddenly crooks his fingers and rubs against a spot that has Castiel arching off of the bed and seeing stars bursting behind his eyelids. When he comes back down to Earth he sees Dean smiling at him with those perfect, kiss-swollen lips.

"Feels good, huh?"

"Yes," Castiel pants. Good is an understatement. "Another finger, please."

Dean obliges and goes back to his task of marking up Castiel's neck, almost as if he knows what an erogenous zone that is for him. That, in addition to Dean repeatedly brushing against his prostate, has Castiel moaning and writhing on the mattress in no time, head pressed back deep into the pillow and fingers clenched in the sheets. It doesn't take long before he feels stretched enough to take Dean's length.

"I'm ready, Dean. Need your knot. _Now_." Maybe Dean was a bit on-target with the 'bossy' remark.

"Can't say no to that, can I?" He pulls his fingers out and leans away from Castiel's neck. His eyes are dark with lust, the tiniest slivers of green just visible around huge, black pupils.

Castiel tries to relax his muscles as the head of Dean's cock breaches his rim. It burns a little but it's not too uncomfortable. He tries to focus on Dean instead, on the taut muscles of his shoulders, the bow of his lips and the curve of his collarbone. Castiel runs his tongue across the protruding arch, tasting the salty skin there.

Dean takes his time inching his way in, and this surprises Castiel. He's used to seeing alphas just take, pounding right into their omegas off the bat. But Dean is different, gentle.

"Am I hurting you?"

Right then, at Dean's concerned words, Castiel is so full of love for the man above him that he feels like he's going to burst open with it. He wants to tell Dean, he wants to scream it to the whole fucking camp but he knows that would scare him away. Instead, he smiles and tells him, "No, Dean."

"Okay, good," he murmurs against his lips as he bottoms out.

The feeling is amazing, perfect, and he moans low in his throat because he finally feels _full_. This is where he's meant to be. Who he's meant to be _with_.

"Oh, God, Cas," Dean groans, and he pulls out nearly all the way before thrusting back in. He sets a tantalizingly slow pace, and it's not nearly enough for Castiel, so he rolls them over until Dean is on his back. The alpha looks surprised at the change of position, but then Cas raises himself up and slams his hips back down, wiping away the shock in Dean's expression and replacing it with unbridled ecstasy. Dean groans low in his throat, and Castiel grabs his shoulder and hauls him up until they're both sitting upright so that their lips can meet hungrily. As Castiel rides him hard into the mattress Dean mouths at his chest, his neck, his ear, his face, everywhere he can reach. He runs fingers through Castiel's hair and pulls gently while his other hand finds Castiel's cock, leaking a generous amount of precome. At the same time he thrusts up, hitting the omega's prostate, causing him to cry out and clench around the cock inside him. Castiel can feel Dean's knot swelling and catching on his rim.

"Fuck, Cas, that's it, baby." Dean's moans are filling the room and Castiel had no idea he was this loud in bed. It's driving him closer and closer to the edge until he feels dangerously close to falling off.

"Bite me. Claim me."

Dean grips his hips and stops his relentless thrusting. "What?" He doesn't look angry, just confused, like that was the last thing he expected to come out of Castiel's mouth.

"Claim me. Dean, _please_." Castiel doesn't want to be _that_ omega, but right now he's not above begging. His heart flutters as Dean bares his teeth. His cock hardens even more in anticipation what will be a dance between pleasure and pain, but when Dean lowers his open mouth to Castiel's neck he only presses his teeth softly before pulling away.

Castiel glares at him angrily. Dean is mocking him. "_Don't tease_." He starts moving away, impending orgasm be damned because he's _pissed_, but Dean just tightens his grip on him.

"Just wait, Cas. We just need to get something straight first."

Castiel decides to humor him and nods. It's partly because he is absolutely, ridiculously in love with the guy, partly because he's so horny he feels like his dick will explode into bloody chunks sluice down the walls, and paint the room red if he doesn't come within the next three minutes.

"If you're mine, you're nobody else's got it?"

The omega lets out a breath he didn't know he was holding and captures Dean's lips in a bruising kiss. "All yours. Got it."

Dean bucks up into him and Castiel starts moving again. It's hard and fast and everything he never knew he needed until now. It's like every neuron in his body is firing at the same time. And when Dean's teeth finally pierce his skin he comes so hard he paints his fucking _chest_ with it. Dean follows right after, shouting out Castiel's name and trembling as his knot fills up, tying them together. He collapses soon after, pulling Castiel, his _mate_, down with him.

Sated, Cas makes a soft, contented sigh and nuzzles into Dean's neck. Warm arms wrap around him and a hand finds its way into his hair.

"You know, I'm not much for cuddling, but this is, uh, this is sorta nice."

"Welcome to the dark side."

"Shut up," Dean says, but he presses a soft kiss to his Castiel's forehead.

Cas falls asleep smiling.


End file.
